Clutch



T. L. FAWICK Nov. 2, 1937.

CLUTCH Filed Oct. 29, 1936 2 Sheets-Sheet l Nov. z, 1937. Y T. L. FAwlcK 2,097,856

` CLUTCH Filed Oct. 29, 1956 2 Sheets-Sheet 2 #ffm atenei Nov. z, 1937 2,097,856

UNITED STATES PATENT OFFICE CLUTCH Thomas L. Fawick, Akron, Ohio, assgnor to In- Y dustrial Clutch Company, a corporation of Wisconsin .Application October 29, 1936, Serial No. 108,156 11 Claims. (Cl. 19232) 'Ihe present invention relates to clutches, and being retained in position independently of lonmore particularly to clutches for coupling drivgitudinal movement of the splined shaft. Thus ing and driven members for conjoint rotation. the driven shaft, as well as the clutch collar and The clutch of the present invention nds utility clutch yoke, can be removed wi-thout disturbing in automotive vehicles, busses, industrial and agrithe clutch construction or its relation to the cultural tractors, trucks and similar vehicles, as driven member. Further, the clutch mecha- Well as in other types of industrial machinery nism itself can be readily removed for inspection, were such members are to be coupled together repair and servicing by removing only the clutch for driving engagement. ring from bolted connection to the driving mem- In my copending application, Serial No. 707,057, ber. filed January 18, 1934, which has matured into In the present construction I have provided Patent No. 2,086,954 there is disclosed a clutch an intermediate member having internal splines construction which broadly embodies some of the in driving engagement with the driven shaft, and features of the present invention. However, the having external helical splines engaged by correpresent application constitutes an improvement spending splines carried by the clutch disc. The in the design and construction of such a clutch helical splined engagement produces the servo mechanism, rendering the clutch more eiicient, action for increasing the pressure of engagement easier to manufacture and assemble, and poswithout increasing the clutch spring pressure, sessed of improved characteristics of operation thus affording smooth, positive engagement and and length of service. l yet allowing relatively easy disengagement. 'Ihe 20 The present invention contemplates. a servo member is preferably packed in grease within a mechanism for utilizing the movement or drivhousing formed by the hub of the clutch disc, ing force of the driving member to impart addithe retainer for the pilot bearing supporting the tional engaging movement of the clutch member end of the driven shaft and the throw-out beartoward the cooperating clutch member after ing assembly. Thus the throw-out bearing is initial engagement. Eccentric binding or chatenclosed within the functional part of the grease tering of the clutch is eliminated by the present housing. construction, and a smooth, velvet-like engage- Other objects and advantages of the present ment is produced. More torque is developed with invention, including the details of the bearing less pressure of the engaging element, because the assemblies and the clutch hub construction, will torque is developed at the largest diameter of the be more apparent to those skilled in the art from clutch, that is, out at the clutch engaging surthe following detailed description which, taken face. in conjunction with the accompanying drawings,

Ihe present clutch is light in weight, balanced, will disclose the particular construction and opand of economical construction. The parts are .eration of a preferred form of the present incapable of being readily machined at small cost, vention.

and may bereadily assembled and supported in In the drawings:

place. Figure 1 is a vertical sectional view, with por- One feature of the present invention is the protions in elevation, of one form of the clutch vision of a clutch construction which may be construction; 40

assembled as a unitary construction, and then Figure 2 is a detail View, partly in section, of employed as a repair or replacement unit for the intermediate hub member; installation in position between the driving and Figure 3 is a sectional view of another embodidriven members, as well as being employed in new ment of the clutch construction; and assemblies. Fig-ure 4 is a detail sectional view of a modi- 45 A still further advantage possessed by the prescation of the hub construction shown in Figure 3. ent construction is the ability to remove the Referring now in detail to the embodiment of driven assembly Without detaching the clutch the invention shown in Figures 1 and 2, I have construction from the driving member, and to provided `a drive shaft 5 having the radial ange reinstall the assembly without any adjustment 6, to which is bolted the flywheel 1 as by means 50 or rearrangement of the clutch or driving asof the ring of bolts 8. The iiywheel 1 carries assembly. This is accomplished by providing a around its outer periphery the ring gear 9 whichv longitudinally removable splined connection beis adapted to have meshing engagement with a tween the clutch hub and the driven shaft, with starting gear for rotating the drive shaft 5 when the pilot bearing and clutch throwout bearing the vehicle or mechanism is to be started, as 5,5

, toward the ywheel 1,

in the case of an automotive or internal combustion engine or the like, and is also provided with the clutch ring member I8, bolted to the radial face of the flywheel 1 by means of a peripheral series of bolts I2.

The clutch ring I0 is provided with a conical surface I3 preferably tapered axially outwardly and adapted to be engaged by the clutch surfaces I4 carried by the clutch member I5. The clutch surfaces I4 comprise a peripheral series of button-like members having circular planar surfaces disposed on the outer periphery of the conical rim portion I6 of the member I5, and riveted thereto as shown at I1. The members I4 take the place of the usual form of clutch lining, and serve to provide for equalized application of torque to the clutch cone I6 by contact with the conical surface'l3 of the flywheel. The clutch member I5 is provided with a radially inwardly extending flange portion I8, riveted adjacent its inner periphery as indicated at I9 to a ring 28, preferably formed of the like, which provides a rigid reinforcing means at the inner end of the clutch disc, and also provides for attachment of the clutch hub thereto, the hub 22 being secured to the ring 28 by means of 1a series of bolts 23 which are secured in tapped openings extending axially through the enlarged portion 24 of the ring 20. The clutch hub 22' is provided with the radially extending ange portion 25 through which the bolts 23 extend, and with an axially extending portion carrying internal splines 26 extending axially thereof and preferably inclined at a slight angle to produce the servo action required.

The hub 22 is preferably formed of cast iron, and at the end opposite the ange 25 is slightly thickened and enlarged to form a recessed shoulder for receiving the oil retaining ring 21 secured to the end of the hub 22` by the set screw 28.

In this embodiment of the invention, the driven member is indicated as the shaft 38, having the reduced pilot portion 32 piloted in the recessed end of the driving member 5 by means of the ball bearings 33, in the usual manner, and having an intermediate splined portion 34 engaged by an intermediate hub member 35 having internal splines engaging with the splines 34 to provide. for driving connection therebetween. The member 35 is shown in more detail tion 31, -jadapted to receive the plug member 38,

which is' piloted in the end of the member 35, and has bearing engagement with the inner race of the bearing assembly 33.

The member 35 is provided with an enlarged portion 39 radially spaced from the lateral surface of the driven member 38, and provided with the external splines 48 adapted to have meshing engagement with the splines 26 of the clutch hub 22. It will be noted that the splines 40 are angled in such manner as to receive the angled splines 26 of the hub '22, whereby upon initial engagement of the friction surfaces I4 with the surface I3, the cone i'disc .member I5 will be threaded axially to the right on the splines, to increase the pressure engagement, thereby increasing the efciency of torque transmission from the flywheel 1 to the driven member 30.

On the external surface of the splined portion 36' of the member 35 there is provided the ansteel or` quently the cone clutch member I5, axially to the right into clutching engagement with the surface I3. I

At its outer end, the hub 22 is recessed to provide a pilot seat for the bearing block or thrust block 46, which may be formed of cast iron or the like, and which has its opposite radial sur` faces ground and polished into parallelism. The

. outer face of the thrust block 46 is engaged by the flanged portion 41 of the clutch actuating collar 48, which is slidably mounted upon the hub portion 49 of the member 58 forming a pilot for the outer end of the driven member 38. The clutch collar 48 is provided on opposite sides with the projecting bosses or nger portions 52 adapted to be engaged by the opposite arms 53 of the clutch yoke 54 mounted for conjoint rotation with the shaft 55 upon which is mounted the clutch operating pedal or similar mechanism. The clutch collar 48 is provided with an oifset extension 5S adapted to form a retaining member for one end` of the spring 51, the spring being biased to normally move the clutch collar 48 outwardly away from engagement with the thrust block 46.

It will be noted that the member 35 is provided, intermediate the enlarged portion 39 and the portion which is splined to engage the driven member 30, with a plurality of angularly extending ports 60 forming grease ducts between .thel

driven member 38 andthe interior of the clutch hub 22. Thus a grease housing is formed between the retaining ring 21 carried by the inner end of the clutch hub 22, and the clutch collar 48 riding on the hub 49 of the member journaling the driven member 38. This vgrease housing retains the grease for the splined engagement between the splines 48 and the splines 26, and also retains grease for the thrust block or bearing`46 which is engaged by the flange 41 of the clutch collar 48.

In the operation of the structure thus far described, the clutch, which is shown in actuated position, is released by rotation of the shaft 55 in a counterclockwise direction. This produces movement of the arms 53 of the clutch yoke 54 against the projections 52 on the clutch collar 48, moving this collar against the thrust block 46 and consequently moving the clutch hub 22 inwardly, against the pressure of spring 45. At the same time, due to the engagement between splines 40 and 26, the hub is rotated in a clockwise direction, asviewed from the right-hand side of the clutch, and the clutch surfaces I4 are disengaged from theclutch surface I3. This results in releasing the driving torque on the clutch member I5 and consequently the clutch` tapered axially outwardly termediate hub ner end of the hub 80 is By disposing the throw-out member or thrust block 46 within a functional part of the grease housing about the splines 40, it isA possibleto provide only a single grease housing for lubrication of the entire clutch mechanism .which requires lubrication, and the ports .60 insure that lubricant will travel from the interiorv of the enlarged portion 39 of the member 35 outwardly for contact with the splines 26 and the splines 40.

Referring now to the embodiment of the invention shown' in Figures 3 and 4, I have provided a driving member 65, having the ange portion 66 to which is bolted the flywheel 61 by means of bolts 68. The flywheel 61 is provided, on its outer radial face, with a clutch ring portion 69, secured thereto by the peripheral series of bolts 10, and having the conical clutch surface 12 toward the flywheel.

Disposed within the ring 69 is the clutch member 13, having the conical rim portion 14 and the radially inwardly extending flange or disc portion 15. The rim portion 14 is provided with clutch lining 16, secured thereto by the countersunk rivets 11, in any usual or preferred manner, while the disc 15 is provided with a radially extending inner portion 18 adapted to be piloted in the outer end of the flange portion 19 of a clutch hub 80, the flange 19 having the axially extending shoulder portion 82 forming an annular seat for the inner definingedge of the portion 18 of the disc 15. The disc is secured to the flange 19 by means of a plurality of stud bolts 83, which also serve to clamp the retaining ring 84 in position about the outer end of the hub 80. The inprovided with a reduced portion 85 adapted to receive the retaining ring 86 which, as shown in Figure 4, closely embraces the external surface 81 of a ring member 88 carried by the forward edge 89 of the intermediate hub member 90. I f desired, a plain ring 88', as shown in Figure 3, may be suitably secured to the end portion 81 member 90 is provided with external splines 92 angled as shown in Figure 3, which are adapted to have engagement with the internal splines 93 formed integral with the hub 60. The splines 92 and 93 are angled in the same manner as described in connection with the embodiment of Figures 1 and 2, in order to produce the servo action in the clutch.

'I'he member 90 is also provided with internal splines 94, which are adapted to have engagement with the splines 95 formed on the inner end of the driven member96. The driven memthe plate 99 and the inner radial ber 96 has a reduced end 91 piloted in the bearing 98 carried within the flywheel 61, as is conventional.

Clamped between the ring 88 and the inner race of the bearing assembly 98 is the spring abutment plate 99, which has a radially extending portion serving to provide a seat for one end of the helically coiled spring |02 biased between surface of the flange 19 of the hub 80. The spring, abutment plate 99 may be apertured, as indicated at |03,

of the hub member 90. This inand, as shown in Figure 4, the bolts 83 maybe replaced by elongated bolts |04, which extend through threaded bosses formed about the apertures |03 of a corresponding plate portion |00', whereby the plate is fixed axially with respect to the flange 19 of the hub 80.

Under such circumstances, the apertures |06.inI the flange 19 are slightly larger than the diameter of the bolts. |04, to allow the ange 19 to have free sliding movement with relation to the bolts, in order to compress the spring |02 when it is desired to disengage the clutch.

The embodiment of the invention shown in l,

Figure 4 distinguishes from that shown in Figure 3 also' in the fact that the retaining ring 84 is not formed as a separate member clamped to the peripheral edge of the disc 15, but the disc is formed from a sheet metal stamping or the like and is provided with an integral oiset retaining ring portion 84', which is carried on the pilot shoulder 82 of the flange 19 in the same manner as described in connection with Figure 3.

In both embodiments of the invention, as i1- lustrated in Figures 3 and 4 a throw-out bearing assembly, indicated generally at H0, is provided, this throw-out bearing comprising the inner race ||2 piloted in the inner end of the flange 19 at the ends of the splines 93, and an outer race 3 which is centered by the retaining ring 84 or the portion 84 of the disc 15' and between which is provided the series of ball members forming the completed bearing. The outer race ||3 is engaged, on its radial surface, by the forward end of the clutch throw-out collar ||4, which has sliding engagement on the hub 5 of the housing member I6. A suitable clutch yoke ||1 carried on the shaft IIB is provided for moving the clutch collar ||4 inwardly to compress the spring 02 and move the disc 15 inwardly to release "the engagement between the surface 12 and the lining 16. 'I'he outer end of the member I6 provides seating engagement for the bearing assembly |20, which engages about the shaft 96, which shaft preferably extends into a transmission housing or a similar driving arwithout increasing the pressure of the spring 02.

It will be noted that by reason of the bearing retaining ring 86, and the fact that the hub 5 closely fits the shaft 96, a housing is provided for the spline-engagement and for the bearing assembly ||0, whereby the throw-out bearing is enclosed within a functional part of this housing.

It is therefore apparent that I have provided a clutch construction ofthe friction type which is efficient in operation, may be assembled and disassembled as a unit with respect to the driving and driven members, and which is economical in manufacture and assembly.

It will be noted, in each embodiment of the invention, that the shaft 96 or 30 can be readily withdrawn from the assembly without disturbing any of the component parts of the clutch, the clutch `remaining in centered position by a portion of reason of the retention therein due to the angle of the surfaces of engagement between the member I5 or 13 of the clutch and the driving member. Thus, the driven elements of the clutch can be assembled to the driving member and the entire clutch assembly then connected as a unit to the driven member. Further, byV removing the bolts which carry the clutch ring on the fiywheel, and removing the driven shaftfrom within the clutch hub assembly,` it is possible to retain the clutch in assembled position and employ it as a unit for connection or disconnection in any desired position between a driving flywheel and a driven shaft. This provides for easy inspection, repair and replacement of the clutch construction.

I do not intend to be limited to the exact details of construction which have been shown and described, inasmuch as these are merely illustrative embodiments of the underlying principles of the invention. The invention is therefore to be limited only as defined by the spirit and scope of the appended claims.

I claim:

1. In combination, a driving member having a conical surface, a. clutch disc having a conical rim, a driven member coaxial of said disc, an intermediate member having splined engagement with said driven member and having a radially spaced overlapping cylindrical portion provided with external -helical splines, a hub member secured to said disc and having internal helical splines engaging said first-named helical splines, a grease retaining ring at the inner end of said hub closely embracing the external surface of said intermediate member forwardly of said splines, a bearing block carried by said hub at the opposite end thereof embracing said driven member, and grease ducts extending through said intermediate member between said radially spaced portion and the portion embraced by said Ting.

2. In combination, a driving member having a conical surface, a driven member coaxial therewith, a clutch disc having a conical rim and a radially inwardly extending flange, a hub rigidly secured to said flange and radially spaced about said driven member, an intermediate member having a forward portion drivingly engaging said driven member and ha'ving a radially enlarged rear portion extending within and drivingly engaged by said hub, an abutment plate carried by and held against forward movement by the forward portion of said intermediate member, spring means-biased between said hub and said plate about the external surface of said hub within the axial length of said disc, a throw-out bearing carried by said hub rearwardly of said intermediate member, and means engaging said bearing for moving said hub axially against the pressure of said spring means.`

3. In combination, a driven shaft having a splined end, a clutch disc having a radial flange, an axially extending hub rigidly secured to the inner edge of said disc and provided with internal helical splines spaced radially of said shaft, an intermediate member having splined connection with said shaft and having a radially' enlarged portion having splined engagement with said hub, means at opposite ends of said hub forming a greas`e housing about said radially enlarged portion, and grease ducts extending radially through said intermediate member between the ends of said hub.

4. An intermediate member for interposition between an internally splined hub of a clutch `disc and a coaxial shaft, comprising a shaft shaft engaging portion having an annular recess receiving a lock ring for a spring abutment plate.

5. A friction clutch ofthe servo type, comprising a driving member having a conical surface, a driven member coaxial therewith, a clutch member therebetween having a conical rim and having an axially extending internally splined hub spaced radially about said driven member, an intermediate member within said hub for transmitting torque from said hub to said driven member, an abutment plate carried by said intermediate member adjacent one end of said hub, spring means biased between said plate and said hub externally of the axially extending portion of said hub, and within said clutch member, and bearing means carried at the opposite end of said hub and adapted to be engaged by the clutch operating mechanism.

6. A friction clutch of the servo type, comprising a driving member having a conical surface, a driven member coaxial therewith, a clutch member therebetween having a conical rim and having an axially extending internally splined hub spaced radially about said driven member, an intermediate member within said hub for transmitting torque from said hub to said driven member, an abutment plate carried by said intermediate member adjacent one end of said hub, spring means biased between said plate and said hub externally of the axially extending pora throw-out bearing at the opposite end of said hub embracing said driven member, and clutch actuating means outwardly of said bearing whereby said bearing is enclosed in the functional part'of the grease housing formed between said hub and said driven member.

7. A hub structure for a friction clutch of the class described, comprising a clutch hub having internal splines and having a radial ange at one end, an intermediate hub member adapted to have splined connection to a driven shaft and having external splines meshing with the hub splines, a radially extending abutment plate adjacent the opposite end of said clutch hub, means carried by said intermediate hub member supporting said plate against axial movement away from said flange, and spring means encircling said hub and biased between said plate and said flange.

8. A hub structure for a. friction clutch of the class described, comprising a clutch hub having internal splines and having a radial flange at one end, an intermediate hub member adapted to have splined connection to a driven shaft and one end, an intermediate hub member adapted to have splined connection to a driven shaft and having external splines meshing with the hub splines, a grease retaining ring embracing said intermediate member and carried by the opposite end of said hub, a throw-out bearing carried by said hub adjacent said ange, and actuating means engaging said bearing and forming with said ring a grease housing for said bearing and said splined connection between said hub and said intermediate member, a, radially extending abutment plate adjacent the opposite end of said clutch hub, and spring means encircling saidI hub and biased between said plate and said flange.

10. In a friction clutch, a clutch member having a radially inwardly extending iiange, a clutch hub having a radially outwardly extendingl ange at one end thereof, an abutment -plate coaxial,v

5 of and spaced from the opposite end of said hub, spring means between said plate and said hub ange, and means clamping said clutch flange to said hub ange and holding said plate in spaced axial relation to said hub ange.

11. Ina friction clutch, a clutch member having a radially inwardly extending flange, a clutch hub having a radially outwardly extending flange at one end thereof, an abutment plate coaxial of and spaced from the opposite end of said hub, spring means between said plate and said hub flange, moans clamping said clutch ange to said hub flange and holding said plate in spaced axial relation to said hub flange, and means extending radially inwardly from said clutch flange for retaining a throw-out bearing in position in the said one end of said hu THOMAS L. FAWICK. 

